在這篇論文中，我們展示一種在冷原子中基於電磁波引發透明的自發四波混頻，並揭露其量子特性。在我們的實驗中，具有時間關聯性的史托克光與反史托克光被同時產生，當史托克光被單光子偵測器偵測到時，反史托克光會在關聯性時間內出現，這段關聯性時間能夠由電磁波引發透明結構控制，我們會使用二階格勞伯相關函數來分析雙光子的時間關聯性。在我們的實驗結果中，最好的訊號背景比能夠達到8，違反了柯西-史瓦茲不等式超過20 倍以上，充分的展現它的量子特性。

In this thesis we demonstrate a kind of electromagnetically-induced-transparencybased (EIT-based) spontaneous four-wave mixing (SFWM) in cold atoms and reveal some quantum characteristics. Two time-correlated photons, Stoke and anti-Stoke photons (or biphoton), are generated simultaneously in our experiment. Once Stoke photon is detected by the single-photon detector, the other photon, anti-Stoke, will appear within the correlated time, which is controllable by EIT structure, forming a heralded twophoton scheme. In our analysis we employ Glauber second-order cross-correlation function to describe its time-correlated property. Among them, the best signal-to-background ratio (SBR) is around 8 in the thesis, which violates Cauchy-Schwarz inequality by more than 20 folds, and it provides sufficient evidence that the results belong to quantum region.

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